The point was that the food was stored a long time (more than a year in some instances) and using mechanical refrigeration, which was new and frightening to some people. It was mentioned that refrigeration (by natural means) had been used before.
“Until we figured out how to use machines to make cold, we were reliant on this very ephemeral, unreliable thing that melted.”
In many areas of the United States ice houses had been used. As a kid, I encountered them in upstate NY in the 1950s. A couple were still in use at that time.
The ice was obtained by harvesting from frozen lakes and ponds during the winter months and was then stored in ice houses which were heavily insulation to keep the ice frozen through warmer months. Some ice houses were built underground. I'm sure the Egyptians, and even the cavemen, had similar setups, although the Egyptians and many early cultures also used other methods of preservation. And I'm sure both Atlas Obscura and Twilley were and are very much aware of the history of refrigeration, and stated as much in very bold type posted in the middle of the article, and which I copied above.
I believe you're aware of all this.
